Do men like their girlfriends to send messages saying they miss him?

It seems that you are really a sensible little girl. . Don't simply say you miss him, you can care about him once in a while, send a message to express your condolences, and remember not to show special impatience or lingering emotions, so that he will feel bored and think you are a child. Remember not to send a dozen or twenty messages a day occasionally. If he happens to be busy, he will feel trouble! If he becomes too close because of returning your messages occasionally, you can improvise at the right time. Just remember to try to match your performance with his reaction.